As device dimensions continue to shrink in semiconductor processing, such as in the increased density of DRAMs, there is a continuing challenge to maintain desired high storage capacitance despite decreasing device size. A principal way of increasing device density is through construction techniques which include three dimensional capacitors such as trenched or stacked capacitors. It is as well recognized that capacitance can be increased by surface roughening of capacitor plates.
This invention comprises an improved technique for roughening a surface to maximize its surface area thereby increasing the capacitance which is available.